Quantum dot material, quantum dot light emitting device, display apparatus and manufacturing method

ABSTRACT

Disclosed are a quantum dot material, a quantum dot light emitting device, a display apparatus and a manufacturing method. The quantum dot material includes: a quantum dot, an anionic ligand, and a linking group linking the quantum dot and the anionic ligand, wherein the anionic ligand is configured to bind to a ring molecule by electrostatic force.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims priority under 35 U.S.C 119 toChinese Patent Application No. 202011193294,6, filed on Oct. 30, 2020,in the China National Intellectual Property Administration. The entiredisclosure of the above application is incorporated herein by reference.

FIELD

The present disclosure relates to the technical field of semiconductors,in particular to a quantum dot material, a quantum dot light emittingdevice, a display apparatus and a manufacturing method.

BACKGROUND

As a new type of light emitting material, quantum dots (QD) have theadvantages of high light color purity, high light emitting quantumefficiency, adjustable light emitting color, long service life, etc.They have become the current research hotspot of new LED light emittingmaterials. Therefore, quantum dot light emitting diodes (QLEDs) usingquantum dot materials as a light emitting layer have become the mainresearch direction of new display devices.

Active matrix quantum dot light emitting diodes (AMQLEDs) have alsoreceived more and more attention due to their potential advantages inwide color gamut and long life. Their research is getting deeper andtheir quantum efficiency is continuously improving, and they havebasically reached the level of industrialization. The further use of newprocesses and technologies to achieve their industrialization has becomea future trend.

SUMMARY

An embodiment of the present disclosure provides a quantum dot material,including: a quantum dot, an anionic ligand, and a linking group linkingthe quantum dot and the anionic ligand, wherein the anionic ligand isconfigured to bind to a ring molecule by an electrostatic force.

In a possible implementation, the ring molecule includes hydrogen atoms,and the anionic ligand is configured to bind to the hydrogen atoms bythe electrostatic force.

In a possible implementation, the quantum dot material further includesa cationic ligand matched with the anionic ligand, wherein the cationicligand is configured to balance a charge of the anionic ligand.

In a possible implementation, the cationic ligand includes one or acombination of:

In a possible implementation, the anionic ligand is one of:

In a possible implementation, the linking group includes one or acombination of:

-   -   —SH—;    -   —COOH—; and    -   —NH₂—;

An embodiment of the present disclosure further provides a quantum dotlight emitting device, including: a base substrate, a functional layerlocated on a side of the base substrate, a quantum dot film layerlocated on a side, facing away from the base substrate, of thefunctional layer, and a connecting layer located between the functionallayer and the quantum dot film layer, wherein the quantum dot film layerincludes a patterned region;

-   -   the quantum dot film layer in the patterned region includes the        quantum dot material provided by embodiments of the present        disclosure; and    -   a region, corresponding to the patterned region, of the        connecting layer includes: a ring molecule, a first structure        connected with the ring molecule, and a connecting structure        connecting the first structure and the functional layer, wherein        the ring molecule and an anionic ligand bind by electrostatic        force, and the first structure is configured to connect or        disconnect the ring molecule and the connecting structure under        preset conditions.

In a possible implementation, the ring molecule has hydrogen atomsthrough which the ring molecule binds to the anionic ligand by theelectrostatic force.

In a possible implementation, the first structure is a photodegradablegroup configured to disconnect the ring molecule from the connectingstructure under ultraviolet irradiation.

In a possible implementation, the photodegradable group includes:carbonyl or epoxy group.

In a possible implementation, the first structure includes a structureformed after a first photocurable group and a second photocurable groupare cross-linked with each other by ultraviolet irradiation, the firstphotocurable group is connected to the ring molecule, and the secondphotocurable group is connected to the connecting structure.

In a possible implementation, the first photocurable group is identicalto the second photocurable group.

In a possible implementation, the first photocurable group includes oneor a combination of:

-   -   alkenyl;    -   alkynyl; and    -   cyano.

In a possible implementation, the ring molecule includes a ring moleculestructure composed of n repeating units connected in sequence, wherein 4

n

10.

In a possible implementation, the ring molecule includes: a polymer ofstyrene or a polymer of a styrene derivative.

In a possible implementation, the ring molecule structure is

wherein 4

n

10; the ring molecule is of a following structure:

In a possible implementation, the connecting structure includes: a silylchain, or a siloxanyl chain; the connecting structure further includes astructure formed by binding one or a combination of following groupsconnected to a silicon atom with the functional layer:

-   -   —Cl;    -   —OCH₃; and    -   —OH.

An embodiment of the present disclosure further provides a displayapparatus, including the quantum dot light emitting device provided byembodiments of the present disclosure.

An embodiment of the present disclosure further provides a manufacturingmethod of the quantum dot light emitting device provided by embodimentsof the present disclosure, including:

-   -   providing a base substrate;    -   forming a functional layer on a side of the base substrate;    -   forming a connecting layer on a side, facing away from the base        substrate, of the functional layer, wherein the connecting layer        includes: a ring molecule, a first structure connected with the        ring molecule, and a connecting structure connecting the first        structure and the functional laver;    -   forming a quantum dot film on a side, facing away from the        functional layer, of the connecting layer, wherein the quantum        dot film includes: a quantum dot, an anionic ligand, and a        linking group linking the quantum dot and the anionic ligand;        and    -   treating the quantum dot film and the connecting layer under        preset conditions to form a patterned quantum dot film layer;    -   the first structure includes a structure formed after a first        photocurable group and a second photocurable group are        cross-linked with each other by ultraviolet radiation, the first        photocurable group is connected to the ring molecule, and the        second photocurable group is connected to the connecting        structure; and the treating the quantum dot film and the        connecting layer under the preset conditions to form the        patterned quantum dot film layer includes:    -   shielding a region where the quantum dot film is removed, and        performing ultraviolet irradiation to make the first        photocurable group and the second photocurable group of an        irradiated region cross-linked, so as to reserve a quantum dot        film in the irradiated region;    -   the forming the connecting layer on the side, facing away from        the base substrate, of the functional layer includes:    -   forming a first sub-connecting layer on the side, facing away        from the base substrate, of the functional layer, wherein the        first sub-connecting layer includes the connecting structure and        the second photocurable group connected with the connecting        structure; and    -   forming a second sub-connecting layer on a side, facing away        from the functional layer, of the first sub-connecting layer,        wherein the second sub-connecting layer includes the ring        molecule and the first photocurable group connected with the        ring molecule;    -   after the quantum dot film and the connecting layer are treated        under the preset conditions to form the patterned quantum dot        film layer, the manufacturing method further includes:    -   reusing the first sub-connecting layer that is not removed from        the shielded region currently as a first sub-connecting layer to        manufacture a quantum dot film of a next emergent light color;    -   the first structure is a photodegradable group; and the treating        the quantum dot film and the connecting layer under the preset        conditions to form the patterned quantum dot film layer        includes:    -   shielding a region where the quantum dot film is reserved, and        performing ultraviolet irradiation to decompose the        photodegradable group in an irradiated region and disconnect the        ring molecule from the connecting structure, so as to remove the        quantum dot film in the irradiated region;    -   the forming the connecting layer on the side, facing away from        the base substrate, of the functional layer includes:    -   forming the connecting layer including the ring molecule, the        photodegradable group and the connecting structure on the side,        facing away from the base substrate, of the functional layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a quantum dot materialprovided by an embodiment of the present disclosure;

FIG. 2 is a schematic structural diagram of another quantum dot materialprovided by an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of a specific quantum dotmaterial provided by an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of another specific quantum dotmaterial provided by an embodiment of the present disclosure;

FIG. 5 is a schematic structural diagram of a quantum dot light emittingdevice provided by an embodiment of the present disclosure;

FIG. 6 is a schematic structural diagram of a connecting layer providedby an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of manufacturing of a quantum dot lightemitting device provided by an embodiment of the present disclosure;

FIG. 8 is a schematic diagram of manufacturing of another quantum dotlight emitting device provided by an embodiment of the presentdisclosure; and

FIG. 9 is a schematic diagram of a manufacturing process of a quantumdot light emitting device provided by an embodiment of the presentdisclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the objectives, technical solutions, and advantages ofthe embodiments of the present disclosure clearer, the technicalsolutions of the embodiments of the present disclosure will be clearlyand fully described in combination with the accompanying drawings of theembodiments of the present disclosure. It is apparent that the describedembodiments are some, but not all, embodiments of the presentdisclosure. Based on the described embodiments of the presentdisclosure, all other embodiments attainable by those ordinary skilledin the art without involving any inventive effort are within the scopeof the present disclosure.

Unless otherwise defined, the technical terms or scientific terms usedin the present disclosure shall have the usual meanings understood bythose with ordinary skills in the field to which the present disclosurebelongs. “First”, “second” and similar words used in the presentdisclosure do not indicate any order, quantity or importance, but areonly used to distinguish different components. “Comprise” or “include”or other similar words mean that the element or item appearing beforethe word covers elements or items listed after the word and theirequivalents, but does not exclude other elements or items. “Connecting”or “connected” or other similar words are not limited to physical ormechanical connections, but may include electrical connections, whetherdirect or indirect. The terms “upper”, “lower”, “left”, “right” and thelike are used merely to denote a relative positional relationship thatmay change accordingly when the absolute position of the object beingdescribed changes.

In order to keep the following description of embodiments of the presentdisclosure clear and concise, the present disclosure omits detaileddescriptions of known functions and known components.

Referring to FIG. 1, an embodiment of the present disclosure provides aquantum dot material, including: a quantum dot QD, an anionic ligand W⁻,and a linking group X linking the quantum dot QD and the anionic ligandW⁻, wherein the anionic ligand W⁻ is configured to bind to a ringmolecule P (as shown in FIG. 6) by electrostatic force. Optionally, thering molecule P contains hydrogen atoms inside, and the anionic ligandW⁻ may bind to the hydrogen atoms in the ring molecule P byelectrostatic force.

In some embodiments of the present disclosure, the anionic ligand W⁻ isnegatively charged, as shown in FIG. 6, some hydrogen atoms on amolecular skeleton of the ring molecule P are concentrated in a ring,electrons contributed by the hydrogen atoms are mostly carbon atoms inthe ring molecule P, and the ring molecule P is in a low-electron state,so that a region in the ring is an electron-deficient space. The regionmay capture some electron-rich compounds or anions, and generate closebinding force with them through the electrostatic force (Coulombinteraction). The region may bind to the anionic ligand W⁻, so that whena pattern of a quantum dot film layer of a quantum dot light emittingdevice is formed through the quantum dot material, a connecting layer isfirstly formed, and the connecting layer includes the ring molecule withthe hydrogen atoms, a first structure connected with the ring molecule,and a connecting structure connecting the first structure and afunctional layer of a base substrate. Because the hydrogen atoms of thering molecule and the anionic ligand of the quantum dot material bind,and are connected or disconnected by the first structure under presetconditions, the quantum dot material in part of a region may be removedas required, while the quantum dot material in part of the region may bereserved, thereby realizing patterning of quantum dots, and solving theproblems of limited patterning of the quantum dots and low resolution ofthe quantum dot light emitting device during ink-jet printing.

In some embodiments, as shown in FIG. 2, the quantum dot materialfurther includes a cationic ligand V⁺ matched with the anionic ligandW⁻, and the cationic ligand V⁺ is configured to balance the charge ofthe anionic ligand W⁻. Optionally, the cationic ligand V⁺ includes oneor a combination of:

In some embodiments, the anionic ligand W⁻ is one of:

In some embodiments, the linking group X includes one or a combinationof —SH—, —COOH—, and —NH₂—.

In order to more dearly understand the quantum dot light emittingmaterial provided by embodiments of the present disclosure, thefollowing detailed description is given.

The quantum dot material in embodiments of the present disclosure adoptsa ligand containing an ionic complex. The structure of the ligand is asshown in FIGS. 3 and 4, and its two ends contain two groups, namely —Xand —YZ. X serves as the linking group, and may be —SH—, —COOH—, —NH2—and other groups that may bind to the quantum dots. Y is a groupcontaining an anionic (or cationic) complex, and Z is a counter ion of Yand mainly plays a role in charge balance. The anionic (or cationic)complex may optionally be an organometallic complex, wherein part of thecomplex may be an organic complex of rare earth metals (such as Ir, La,Nd and Eu) and other metals (such as Cu, In, Pb and Pt). The organiccomplex may be: o-phenanthroline, 2-phenylpyridine, phenyloxadiazolepyridine, fluorophenylpyridine, bipyridine, etc. and their derivatives,and binds to the metals to form the cationic complex (Y⁺), for example,

The organic complex may further be tetrakis(pentafluorophenyl)boronicacid, tetrakis[(trifluoromethyl)phenyl]boronic acid,tetrakis[bis(trifluoromethyl)phenyl]boronic acid,hexa(pentafluorophenyl)phosphoric acid,hexa[trifluoromethyl)phenyl]phosphoric acid,hexa[bis(trifluoromethyl)phenyl]phosphoric acid, etc. and theirderivatives, and binds to metalsto form the anionic complex (Y⁻), for example,

If the cationic complex Y⁺ is selected, its counter anion Z may be agreat-steric-hindrance anionic complex, or small molecules such as ClO₄⁻, Cl⁻, PF₆ ⁻ and BF₃ ⁻, at this moment, Z⁻ may be used as the anionicligand W⁻ that binds to protons in the ring molecule, and Y⁺ is used asthe cationic ligand V⁺. If the anionic complex Y⁻ is selected, itscounter cation Z may be a great-steric-hindrance cationic complex, orsmall molecules such as NH₄ ⁺ and Na⁺, at this moment, Y⁻ may be used asthe anionic ligand W⁻ that binds to the protons in the ring molecule,and Z⁺ is used as the cationic ligand V⁺.

Based on the same inventive concept, an embodiment of the presentdisclosure further provides a quantum dot light emitting device, asshown in FIGS. 5 and 6, wherein FIG. 6 is an enlarged structuralschematic diagram of a connecting layer 3. The quantum dot lightemitting device includes: a base substrate 1, a functional layer 2located on one side of the base substrate 1, a quantum dot film layer 4located on a side, facing away from the base substrate 1, of thefunctional layer 2, and the connecting layer 3 located between thefunctional layer 2 and the quantum dot film layer 4. The quantum dotfilm layer 4 includes a patterned region 41 and a removed region 42.

The quantum dot film layer 4 in the patterned region 41 includes thequantum dot material provided by embodiments of the present disclosure.That is, the quantum dot material includes: a quantum dot QD, an anionicligand W⁻, and a linking group X linking the quantum dot QD and theanionic ligand W⁻, wherein the anionic ligand W⁻ is configured to bindto hydrogen atoms in a ring molecule.

A region, corresponding to the patterned region 41, of the connectinglayer 3 includes: the ring molecule P, a first structure M connectedwith the ring molecule P, and a connecting structure Q connecting thefirst structure M and the functional layer 2. The ring molecule P andthe anionic ligand W⁻ bind by electrostatic force, and the firststructure M is configured to connect or disconnect the ring molecule Pand the connecting structure Q under preset conditions. Optionally, thering molecule P has the hydrogen atoms through which the ring molecule Pbinds to the anionic ligand W⁻ by the electrostatic force.

In some embodiments, the connecting layer 3 is formed on the side,facing away from the base substrate, of the functional layer, theconnecting layer 3 includes: the ring molecule P with the hydrogenatoms, the first structure M connected with the ring molecule P, and theconnecting structure Q connecting the first structure M and thefunctional layer 2, protons in the ring molecule P may bind to theanionic ligand W⁻ of the quantum dot material, the first structure M mayconnect or disconnect the ring molecule P and the connecting structure Qunder preset conditions, and therefore the quantum dot material in partof the region may be removed while the quantum dot material in part ofthe region may be reserved as required, thereby realizing patterning ofquantum dots, and solving the problems of limited patterning of thequantum dots and low resolution of the quantum dot light emitting deviceduring ink-jet printing.

In some embodiments, a first electrode layer (not shown in the figures)may be disposed between the functional layer 2 and the base substrate 1,and a second electrode layer (not shown in the figures) may be disposedon a side, facing away from the connecting layer 3, of the quantum dotfilm layer 4. Optionally, the first electrode layer may be a cathode,and the second electrode layer may be an anode. The functional layer 2may be an electron transport layer, and a material of the electrontransport layer may be zinc oxide. The surface of zinc oxide may containgroups such as —OH and —O. The removed region 42 may be a region where aquantum dot film of the current emergent light color needs to be removedin the patterning process of the quantum dot film of one emergent lightcolor. The removed region 42 may be used to manufacture a quantum dotpattern of the next emergent light color.

In some embodiments, as shown in FIG. 7, the first structure M is aphotodegradable group, and the photodegradable group is configured todisconnect the ring molecule P from the connecting structure Q underultraviolet irradiation. Optionally, the photodegradable group includes:carbonyl or epoxy group. In the embodiment of the present disclosure,since the first structure M is the photodegradable group, when thequantum dot film is patterned, the region where the quantum dot filmneeds to be reserved (as the patterned region 41 in FIG. 7) may beshielded through a mask, while the region where the quantum dot filmneeds to be removed (as the removed region 42 in FIG. 7) may be exposedto ultraviolet irradiation. After the ultraviolet irradiation, in theregion where the quantum dot film needs to be reserved (as the patternedregion 41 in FIG. 7), the first structure M has no broken bond, and thequantum dot film is reserved; while in the region where the quantum dotfilm needs to be removed (as the removed region 42 in FIG. 7), the firststructure M has a broken bond, and the quantum dot film is removed,thereby realizing the patterning of the quantum dot film.

In some embodiments, as shown in FIG. 8, the first structure M includesa structure formed after a first photocurable group M1 and a secondphotocurable group M2 are cross-linked with each other under ultravioletirradiation, wherein the first photocurable group M1 is connected to thering molecule P, and the second photocurable group M2 is connected tothe connecting structure Q. Optionally, the first photocurable group M1and the second. photocurable group M2 are the same. Optionally, thefirst photocurable group M1 includes one or a combination of thefollowing: alkenyl, alkynyl; and cyano. In the embodiment of the presentdisclosure, since the first structure M includes the structure formedafter the first photocurable group M1 and the second photocurable groupM2 are cross-linked with each other under ultraviolet irradiation, whenthe quantum dot film is patterned, the region where the quantum dot filmneeds to be reserved may be exposed to ultraviolet irradiation, whilethe region where the quantum dot film needs to be removed may beshielded by a mask. After the ultraviolet irradiation, in the regionwhere the quantum dot film needs to be reserved, the first photocurablegroup M1 and the second photocurable group M2 are cross-linked with eachother, and the quantum dot film is cured and cross-linked, and isreserved; while in the region where the quantum dot film needs to beremoved, the first photocurable group M1 and the second photocurablegroup M2 are not cross-linked with each other, the first photocurablegroup M1 connected with the ring molecule P and the quantum dot QD maybe cleaned and removed in the subsequent cleaning process, and then thequantum dot film is also removed, thereby realizing the patterning ofthe quantum dot film.

In some embodiments, the ring molecule P includes a ring moleculestructure composed of n repeating units connected in sequence, where 4

n

10. Optionally, the ring molecule P includes: a polymer of styrene or apolymer of a styrene derivative. Specifically, the ring moleculestructure may be

where 4

n

10. Specifically, the ring molecule P is of the following structure:

where n=5. That is, the ring molecule P consists of a plurality ofrepeating units connected one by one to form a ring, with a hollowstructure in the middle and containing more protons, so the ringmolecule P may tightly bind to an anion.

In some embodiments, as shown in FIG. 6, the connecting structure Qincludes: a silyl chain or a siloxanyl chain. Optionally, the connectingstructure Q further includes a structure formed by binding one or acombination of following groups connected to the silicon atoms with thefunctional layer: —Cl; —OCH₃; and —OH, and a —Si—O— group is formedafter binding to the functional layer. Optionally, the connectingstructure Q may be one of silane derivatives containing the silyl chainor the siloxanyl chain at the end of a side chain of the ring moleculeP, and Si—Cl, Si—OH, Si—OCH₃ and the like at one end of a silicon oxygenbond may directly bind to —OH, —O and other groups on the surface of thezinc oxide functional layer 2.

Based on the same inventive concept, an embodiment of the presentdisclosure further provides a display apparatus, including the quantumdot light emitting device provided by the embodiment of the presentdisclosure.

Based on the same inventive concept, referring to FIG. 9, an embodimentof the present disclosure further provides a manufacturing method of thequantum dot light emitting device provided in embodiments of the presentdisclosure. The method includes:

-   -   S100, a base substrate is provided;    -   S200, a functional layer is formed on one side of the base        substrate;    -   S300, a connecting layer is formed on one side, facing away from        the base substrate, of the functional layer, wherein the        connecting layer includes: a ring molecule, a first structure        connected with the ring molecule, and a connecting structure        connecting the first structure and the functional layer;    -   S400, a quantum dot film is formed on a side, facing away from        the functional layer, of the connecting layer, wherein the        quantum dot film includes: a quantum dot, an anionic ligand, and        a linking group linking the quantum dot and the anionic ligand;        and    -   S500, treating the quantum dot film and the connecting layer        under preset conditions to form a patterned quantum dot film        layer.

In some embodiments, the first structure M is a photodegradable group.For step S500, treating the quantum dot film and the connecting layerunder the preset conditions to form the patterned quantum dot film layerincludes: the region where the quantum dot film is reserved is shielded,and ultraviolet irradiation is performed to decompose thephotodegradable group in an irradiated region and disconnect the ringmolecule from the connecting structure, so as to remove the quantum dotfilm. Correspondingly, for step S300, forming the connecting layer onthe side, facing away from the base substrate, of the functional layerincludes: the connecting layer including the ring molecule, thephotodegradable group and the connecting structure is formed on theside, facing away from the base substrate, of the functional layer. Thatis, the connecting layer containing the ring molecule, thephotodegradable group, and the connecting structure may be directlyformed in one step.

In some embodiments, the first structure M includes a structure formedafter a first photocurable group and a second photocurable group arecross-linked with each other under ultraviolet irradiation, wherein thefirst photocurable group is connected to the ring molecule, and thesecond photocurable group is connected to the connecting structure. Forstep S500, treating the quantum dot film and the connecting layer underthe preset conditions to form the patterned quantum dot film layerincludes: the region where the quantum dot film is removed is shielded,and ultraviolet irradiation is performed to make the first photocurablegroup and the second photocurable group in the irradiated regioncross-linked, so as to reserve the quantum dot film. Correspondingly,for step S300, forming the connecting layer on the side, facing awayfrom the base substrate, of the functional layer includes: forming afirst sub-connecting layer on the side, facing away from the basesubstrate, of the functional layer, wherein the first sub-connectinglayer includes the connecting structure and the second photocurablegroup connected with the connecting structure; and a secondsub-connecting layer is formed on a side, facing away from thefunctional layer, of the first sub-connecting layer, wherein the secondsub-connecting layer includes the ring molecule and the firstphotocurable group connected with the ring molecule. That is, theconnecting layer may be formed in two steps. Correspondingly, after stepS500, namely after the quantum dot film and the connecting layer aretreated under the preset conditions to form the patterned quantum dotfilm layer, the manufacturing method further includes: the firstsub-connecting layer that is not removed from the shielded regioncurrently is reused as a first sub-connecting layer to manufacture aquantum dot film of a next emergent light color. That is, in the regionwhere the quantum dot film needs to be removed (namely the shieldedregion in the manufacturing process of the quantum dot film of thecurrent emergent light color), the connecting structure Q connected withthe functional layer 2 and the second photocurable group M2 connectedwith the connecting structure Q may be reserved, and reused as astructure to manufacture the next type of quantum dot film, therebysimplifying the process steps.

In order to more clearly understand the manufacturing method of thequantum dot light emitting device provided by embodiments of the presentdisclosure, the following detailed description is given.

In some embodiments, the quantum dot light emitting device ismanufactured in a mode that a cationic complex Y⁺ is used, its counteranion is PF₆ ⁻ and ClO₄ ⁻, the ring molecule P is formed by connecting nrepeating units, where n=5, and the first structure M adopts thephotodegradable group, as shown in FIG. 7.

Step 1, a first electrode layer is deposited on a specific basesubstrate 1, wherein the base substrate 1 may be glass or a flexible PETsubstrate, and the first electrode layer may be transparent ITO, FTO, aconductive polymer, etc., or an opaque metal electrode such as Al andAg, and is used as a cathode layer.

Step 2, ZnO or an Mg, Al, Zr or Y doped ZnO film is deposited on thefirst electrode layer by magnetron sputtering as an electron transportlayer (functional layer 2), wherein the thickness of the electrontransport layer of each sub-pixel may be deposited as required, thethickness is 50 nm-300 nm.

Step 3, the connecting layer 3 is prepared, a silane derivativecontaining the ring molecule P is dissolved in tetrahydrofuran (THF),mixed with hydrochloric acid, stirred for use, filtered with apolytetrafluoroethylene (PTFE) filter membrane before preparation, anddiluted in epoxy hexane; and the prepared solution is dropped on asurface with the functional layer 2 formed thereon, or, the basesubstrate 1 with the functional layer 2 formed thereon is soaked in theprepared solution; and after 5 min-20 min at a room temperature, thebase substrate 1 is removed, and washed with epoxy hexane, so that thedisconnected quantum dot QD and the remaining structure of theconnecting layer 3 in the removed region 42 are washed away together.

Step 4, the quantum dot film (20 nm-50 nm) is deposited, wherein thequantum dot film may bind to the protons in the ring molecule P.

Step 5, the part where the quantum dot film needs to be reserved isshielded by adopting a photolithography process, the position irradiatedby ultraviolet light (UV) may be washed away with a solvent because thering molecule P is disconnected from the base substrate 1, and theposition not irradiated by UV is reserved. Optionally, the remainingstructure (such as the connecting structure Q) in the region irradiatedby UV may be further removed, so as to manufacture the pattern of thequantum dot film of the next emergent light color in the region.

Step 6, quantum dot film layers with other emergent light colors areprepared using similar processes.

Step 7, a hole transport layer, a hole injection layer, and a secondelectrode layer are deposited in sequence, wherein the second electrodelayer may be Al, Ag, etc., or, IZO may be deposited by magnetronsputtering with the thickness of 10 nm-100 nm.

In another possible embodiment, the quantum dot light emitting device ismanufactured in a mode that a cationic complex Y⁺ is adopted, itscounter anion is PF₆ ⁻, ClO₄ ⁻, etc., the ring molecule P is formed byconnecting n repeating units, where n=5, and the first structure Mincludes the first photocurable group M1 and the second photocurablegroup M2, as shown in FIG. 8.

Step 1, a first electrode layer is deposited on a specific basesubstrate 1, wherein the base substrate 1 may be glass or a flexible PETsubstrate, and the first electrode layer may be transparent ITO, FTO, aconductive polymer, etc., or an opaque metal electrode such as Al andAg, and is used as a cathode layer.

Step 2, ZnO or an Mg, Al, Zr or Y doped ZnO film is deposited on thefirst electrode layer by magnetron sputtering as an electron transportlayer (functional layer 2), wherein the thickness of the electrontransport layer of each sub-pixel may be deposited as required, thethickness is 50 nm-300 nm.

Step 3, a layer of silane derivative (used as the connecting structureQ) of the silyl chain or the siloxanyl chain containing the secondphotocurable group M2, such as alkene, alkyne or cyano, at the tail endis deposited firstly; the silane derivative containing the ring moleculeP is dissolved in tetrahydrofuran (THF), mixed with hydrochloric acid,stirred for later use, filtered with a polytetrafluoroethylene (PTFE)filter membrane before preparation, and diluted in epoxy hexane; theprepared solution is dropped on the surface of the base substrate 1 withthe functional layer 2 formed thereon, or the base substrate 1 with thefunctional layer 2 formed thereon is soaked in the prepared solution;and after 5 min-20 min at a room temperature, the base substrate 1 isremoved, and washed with epoxy hexane, and the unfixed ring molecule Pand the remaining structure of the connecting layer 3 in the shieldedregion are washed away together.

Step 4, the connecting layer 3 is deposited. It should be noted thatthis step is only for film formation, no reaction condition exists, andthe first photocurable group M1 and the second photocurable group M2 arecross-linked after the next step of ultraviolet irradiation.

Step 5, the part where the quantum dot film does not need to bedeposited is shielded by adopting a photolithography process, theposition irradiated by UV may not be washed away due to cross-linkingbetween a side chain of the ring molecule P and the base substrate 1with the functional layer 2 formed thereon, and the position notirradiated by UV may be washed away due to non-cross-linking. In theregion where the quantum dot film needs to be removed in themanufacturing process of the quantum dot film of the current color (thatis, the shielded region in the manufacturing process of the quantum dotfilm of the current emergent light color), the connecting structure Qconnected with the functional layer 2 and the second photocurable groupM2 connected with the connecting structure Q may be reserved, and reusedas a first sub-connecting layer to manufacture the next type of quantumdot film, thereby simplifying the process steps.

Step 6, the quantum dot film (20 nm-50 nm) is deposited, wherein thequantum dot film may bind to the part where the ring molecule P isreserved.

Step 7, quantum dot film layers with other emergent light colors areprepared using similar processes.

Step 8, a hole transport layer, a hole injection layer, and a secondelectrode layer are deposited in sequence, wherein the second electrodelayer may be Al, Ag, etc., or, IZO may be deposited by magnetronsputtering with the thickness of 10 nm-100 nm.

The beneficial effects of embodiments of the present disclosure are asfollows: in embodiments of the present disclosure, the connecting layer3 is formed on the side, facing away from the base substrate, of thefunctional layer, the connecting layer 3 includes: the ring molecule P,the first structure M connected with the ring molecule P, and theconnecting structure Q connecting the first structure M and thefunctional layer 2, the ring molecule P can bind to the anionic ligandW⁻ of the quantum dot material by the electrostatic force, the firststructure M may connect or disconnect the ring molecule P and theconnecting structure Q under preset conditions, and therefore thequantum dot material in part of the region can be removed while thequantum dot material in part of the region can be reserved as required,thereby realizing patterning of the quantum dots, and solving theproblems of the limited patterning of the quantum dots and the lowresolution of the quantum dot light emitting device during ink-jetprinting.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present disclosurewithout departing from the spirit or scope of the present disclosure.Thus, it is intended that the present disclosure cover the modificationsand variations provided they come within the scope of the appendedclaims and their equivalents.

What is claimed is:
 1. A quantum dot material, comprising: a quantumdot, an anionic ligand, and a linking group linking the quantum dot andthe anionic ligand, wherein the anionic ligand is configured to bind toa ring molecule by an electrostatic force.
 2. The quantum dot materialaccording to claim 1, wherein the ring molecule comprises hydrogenatoms, and the anionic ligand is configured to bind to the hydrogenatoms by the electrostatic force.
 3. The quantum dot material accordingto claim 1, further comprising a cationic ligand matched with theanionic ligand, wherein the cationic ligand is configured to balance acharge of the anionic ligand.
 4. The quantum dot material according toclaim 3, wherein the cationic ligand comprises one or a combination of:


5. The quantum dot material according to claim 1, wherein the anionicligand is one of:


6. The quantum dot material according to claim 1, wherein the linkinggroup comprises one or a combination of: —SH—; —COOH—; and —NH₂—.
 7. Aquantum dot light emitting device, comprising: a base substrate, afunctional layer arranged on a side of the base substrate, a quantum dotfilm layer arranged on a side, facing away from the base substrate, ofthe functional layer, and a connecting layer arranged between thefunctional layer and the quantum dot film layer, wherein the quantum dotfilm layer comprises a patterned region; the quantum dot film layer inthe patterned region comprises the quantum dot material according toclaim 1; and a region, corresponding to the patterned region, of theconnecting layer comprises: a ring molecule, a first structure connectedwith the ring molecule, and a connecting structure connecting the firststructure and the functional layer, wherein the ring molecule and ananionic ligand bind by the electrostatic force, and the first structureis configured to connect or disconnect the ring molecule and theconnecting structure under preset conditions.
 8. The quantum dot lightemitting device according to claim 7, wherein the ring molecule hashydrogen atoms through which the ring molecule binds to the anionicligand by the electrostatic force.
 9. The quantum dot light emittingdevice according to claim 7, wherein the first structure is aphotodegradable group configured to disconnect the ring molecule fromthe connecting structure under ultraviolet irradiation.
 10. The quantumdot light emitting device according to claim 9, wherein thephotodegradable group comprises: carbonyl or epoxy group.
 11. Thequantum dot light emitting device according to claim 7, wherein thefirst structure comprises a structure formed after a first photocurablegroup and a second photocurable group are cross-linked with each otherby ultraviolet irradiation, the first photocurable group is connected tothe ring molecule, and the second photocurable group is connected to theconnecting structure.
 12. The quantum dot light emitting deviceaccording to claim 11, wherein the first photocurable group is identicalto the second photocurable group.
 13. The quantum dot light emittingdevice according to claim 12, wherein the first photocurable groupcomprises one or a combination of: alkenyl; alkynyl; and cyano.
 14. Thequantum dot light emitting device according to claim 7, wherein the ringmolecule comprises a ring molecule structure composed of n repeatingunits connected in sequence, wherein 4

n


10. 15. The quantum dot light emitting device according to claim 14,wherein the ring molecule comprises: a polymer of styrene or a polymerof a styrene derivative.
 16. The quantum dot light emitting deviceaccording to claim 14, wherein the ring molecule structure is

wherein the ring molecule is of a following structure:


17. The quantum dot light emitting device according to claim 7, whereinthe connecting structure comprises: a silyl chain, or a siloxanyl chain;wherein the connecting structure further comprises a structure formed bybinding one or a combination of following groups connected to a siliconatom with the functional layer: —Cl; —OCH₃; and —OH.
 18. A displayapparatus, comprising the quantum dot light emitting device according toclaim
 7. 19. A manufacturing method of the quantum dot light emittingdevice according to claim 7, comprising: providing a base substrate;forming a functional layer on a side of the base substrate; forming aconnecting layer on a side, facing away from the base substrate, of thefunctional layer, wherein the connecting layer comprises: a ringmolecule, a first structure connected with the ring molecule, and aconnecting structure connecting the first structure and the functionallayer; forming a quantum dot film on a side, facing away from thefunctional layer, of the connecting layer, wherein the quantum dot filmcomprises: a quantum dot, an anionic ligand, and a linking group linkingthe quantum dot and the anionic ligand; and treating the quantum dotfilm and the connecting layer under preset conditions to form apatterned quantum dot film layer.
 20. The manufacturing method accordingto claim 19, wherein the first structure comprises a structure formedafter a first photocurable group and a second photocurable group arecross-linked with each other by ultraviolet radiation, the firstphotocurable group is connected to the ring molecule, and the secondphotocurable group is connected to the connecting structure; and thetreating the quantum dot film and the connecting layer through thepreset conditions to form the patterned quantum dot film layercomprises: shielding a region where the quantum dot film is removed, andperforming ultraviolet irradiation to make the first photocurable groupand the second photocurable group of an irradiated region cross-linked,so as to reserve a quantum dot film in the irradiated region; whereinthe forming the connecting layer on the side, facing away from the basesubstrate, of the functional layer comprises: forming a firstsub-connecting layer on the side, facing away from the base substrate,of the functional layer, wherein the first sub-connecting layercomprises the connecting structure and the second photocurable groupconnected with the connecting structure; and forming a secondsub-connecting layer on a side, facing away from the functional layer,of the first sub-connecting layer, wherein the second sub-connectinglayer comprises the ring molecule and the first photocurable groupconnected with the ring molecule; wherein after the quantum dot film andthe connecting layer are treated under the preset conditions to form thepatterned quantum dot film layer, the manufacturing method furthercomprises: reusing the first sub-connecting layer that is not removedfrom the shielded region as a first sub-connecting layer to manufacturea quantum dot film of a next emergent light color; wherein the firststructure is a photodegradable group; and the treating the quantum dotfilm and the connecting layer under the preset conditions to form thepatterned quantum dot film layer comprises: shielding a region where thequantum dot film is reserved and performing ultraviolet irradiation todecompose the photodegradable group in an irradiated region anddisconnect the ring molecule from the connecting structure, so as toremove the quantum dot film in the irradiated region; wherein theforming the connecting layer on the side, facing away from the basesubstrate, of the functional layer comprises: forming the connectinglayer comprising the ring molecule, the photodegradable group and theconnecting structure on the side, facing away from the base substrate,of the functional layer.